SIMS 213: User Interface Design & Development Marti Hearst Tues Feb 20, 2001

Slide adapted from James Landay Why Do We Prototype? Get feedback on our design faster – saves money Experiment with alternative designs Fix problems before code is written Keep the design centered on the user

Slide adapted from James Landay Fidelity in Prototyping Fidelity refers to the level of detail High fidelity ? – prototypes look like the final product Low fidelity ? – artists renditions with many details missing

Paper prototyping Main idea: – Sketch out prototypes of the interface on paper – Potential users “walk through” task scenarios using the paper interface – A designer “plays computer” – Change the design on-the-fly if helpful Widely practiced in industry – Sounds silly at first, but is surpringly effective – Helps people work together on the design Readings by Rettig, Cooper, Klee, Spool’s group – This discussion primarily follows Rettig’s article

Slide adapted from James Landay The Materials Large, heavy, white paper (11 x 17) 5x8 in. index cards Post-it notes Tape, stick glue, correction tape Pens & markers (many colors & sizes) Transparencies (including colored) Colorforms (toy stores) Scissors, X-acto knives, etc.

Slide adapted from James Landay Constructing the Model Set a deadline – don’t think too long - build it! Draw a window frame on large paper Put different screen regions on cards – anything that moves, changes, appears/disappears Ready response for any user action – e.g., have those pull-down menus already made Use photocopier to make many versions

Slide adapted from James Landay Preparing for a Test Select your participants – understand background of intended users – use a questionnaire to get the people you need – don’t use friends or family Prepare scenarios that are – typical of the product during actual use – make prototype support these (small, yet broad) Practice running the computer to avoid “bugs”

Slide adapted from James Landay Conducting a Test Four testers (preferable) – greeter - puts users at ease & gets data – facilitator - only team member who speaks gives instructions & encourages thoughts, opinions – computer - knows application logic & controls it always simulates the response, w/o explanation – observer(s) - take notes & recommendations Typical session is approximately 1 hour – preparation, the test, debriefing

Slide adapted from James Landay Conducting a Test (cont.) Greet – get forms filled, assure confidentiality, etc. Test – facilitator hands written tasks to the user must be clear & detailed – facilitator keeps getting “output” from participant “What are you thinking right now?”, “Think aloud” – observe -> no “a-ha”, laugh, gape, etc.

Slide adapted from James Landay Conducting a Test (cont.) Debrief – fill out post-evaluation questionnaire – ask questions about parts you saw problems on – gather impressions – give thanks

Slide adapted from James Landay Evaluating Results Sort & prioritize observations – what was important? – lots of problems in the same area? Create a written report on findings – gives agenda for meeting on design changes Make changes & iterate

Potential difficulties Interfaces with large focus on content – Dynamic or static; both are ill-suited Use word processor for large sets of text – For search/database applications Have pre-planned searches (not very realistic) Write up search results on the fly – Maybe have a printer nearby that can produced typed results Bottom line: can only prototype the main interaction this way; search needs to be hooked up to really test the search mechanism

Potential difficulties Interfaces that use animation / dynamic graphics – IUE’s answer: maybe it isn’t all that usable to have flash – Broader answer: Only testing the main functionality, not the finer points The interface should also work without the flash – Use transparencies, etc, for important rollovers.

Slide adapted from James Landay Advantages of Low-fi Prototyping Takes only a few hours – no expensive equipment needed Can test multiple alternatives Can change the design as you test – If users are trying to use the interface in a way you didn’t design it – go with what they think! Adapt! Allows designers to work together

Examples For more detail, see History/Bookmark web browser interface Collection Selection Interface Knowledge Management Interface Airline Reservation interface

Sho, Shamma, von Krogh, Johnstad

Sho, Shamma, von Krogh, Johnstad

Sho, Shamma, von Krogh, Johnstad

Costa, Chopra, Orr, Stetson

Brandt, Falk, McMahon

Hernandez, Liang

Designing a content page Using low-fi techniques Combine low-fi paper prototyping and card sorting – Idea from Peter Merholtz Start with a page with all the features you might want Cut it up into pieces Have people arrange the components – One set of users sorts into groups, as in card sorting for categories – Another set of users lays out the information in a way that would work well for them given certain tasks.

Designing a content page using low-fi techniques Additional hints – Have a discard pile to get rid of things Helps decide what to discard, put toward bottom – Allow additions, reformatting, etc. (People probably will only rarely add) – Back up the paper with sturdy paper Aids re-use – Make it easy to draw and change grouping relationships Put a whiteboard on a table and put pieces of paper on top of that; use whiteboard pens to draw relationships Use colorforms or felt to make this work on a vertical surface

Slide adapted from James Landay Wizard of Oz Technique Faking the interaction. – The term is from the film “The Wizard of OZ” – “the man behind the curtain” Main idea: – The participant interacts with a computer interface as usual – Instead of the program writing back, a person writes back pretending to be the computer Very useful for assessing hard-to-implement features – Speech & handwriting recognition interface design

DENIM A research effort at UCB intended to combine the best of paper and computers – Allows for free-hand sketching – But also allows for undo, copies, etc. Has a storyboarding facility – Can help design the interactions for the person playing computer